Is gas giant life feasible?

[speaker-to-trolls]

An alien environment which is beloved of many scifi writers is the atmosphere of a gas giant, where one can imagine an aerial ecosystem which might look a bit like an aquatic ecosystem developing. But I've been thinking about there seem to be a few barriers to life evolving in a gas giant atmosphere.
1: Since this is air rather than water, the useful molecules will be a lot more widely dispersed, could make things difficult.
2:There is little liquid water in which chemical reactions can take place, and what there is is transient, which leads me to
3:Any given environment in which life could evolve is much less stable than it would be in water on a terrestrial planet, molecules could be dispersed and conditions sharply altered at any moment, making the accumulation of traits and development of life somewhat difficult.

Basically prompted by remembering an old tv program about astrobiology (Natural History of an Alien was the name) in which one of the talking heads commented on this idea with the phrase "I think we know from here on Earth that life needs something more substantial than a cloud". Are there ways around these criticisms which I'm not aware of? (I'd suggest that it might be more faesible for life to develope in the lower atmosphere, but I don't know enough about what is supposed to be down there).

Fixed your typo. ~S

[B5B7]

There are claims from decades ago about where life couldn't possibly live, and then extremophiles were discovered.
I suggest you read the book 'What Does a Martian Look Like?: THe Science of Extraterrestiral Life' by Jack Cohen and Ian Stewart, to expand your horizons.

[Johonebesus]

Isn't Jupiter supposed to have crystallized hydrogen on the outside of its core? I would think that as one gets lower in the atmosphere the gases would get more compressed and therefore thicker, eventually passing through the consistency of water. It still wouldn't have the same chemical properties, but the fluid would be more substantial than clouds.

[speaker-to-trolls]

There are claims from decades ago about where life couldn't possibly live, and then extremophiles were discovered.
I suggest you read the book 'What Does a Martian Look Like?: THe Science of Extraterrestiral Life' by Jack Cohen and Ian Stewart, to expand your horizons.

I know about extremophiles. The thing is they live in extreme liquid environments, there's a difference between an extreme environment and an extreme environment which can change at any moment and has very thinly spread nutrients.

[Sky Captain]

In a gas giant atmosphere there are very strong winds which would likely disperse any complex molecules that could form there. Perhaps deeper where conditions are more stable some sort of life might form, but then it`s probably going to be something very different from life here on Earth.

Also there is a question is there enough carbon in a gas giant for carbon based life to form, I think gas giants are mostly hydrogen and helium with some small amounts of other inert gases.

Anyway moons of a gas giant seems to be more preferable place for life to evolve than gas giant itself.

[Fingolfin_Noldor]

Isn't Jupiter supposed to have crystallized hydrogen on the outside of its core? I would think that as one gets lower in the atmosphere the gases would get more compressed and therefore thicker, eventually passing through the consistency of water. It still wouldn't have the same chemical properties, but the fluid would be more substantial than clouds.

I'm not sure what is meant by crystallized, but hydrogen at high pressure conducts and is called metallic hydrogen.

I'm not too aware about the mechanics, but whether or not life can exist in such conditions hinges on what sources of energy are available and whether there are biological processes that exist to metabolize and harness the said energy sources.

[Broomstick]

Just a couple responses:

1: Since this is air rather than water, the useful molecules will be a lot more widely dispersed, could make things difficult.

While the upper levels of the atmosphere of a gas giant would be at the same pressure or lower than Earth's, the deeper you go the greater the pressure. At some point, the density of the gasses will approach and then exceed that of water on the Earth's surface. In fact, at some point the gasses will probably be in a state better described as liquid - after all, we liquify gasses by compression all the time on Earth for easier and more compact transport of them for industrial purposes.

Also there is a question is there enough carbon in a gas giant for carbon based life to form, I think gas giants are mostly hydrogen and helium with some small amounts of other inert gases.

Although the percentage of heavier elements like carbon may be very small in a gas giant, gas giants are HUGE so the absolute amounts of such eelements may exceed those found on a small, rocky planet like ours. Of course, to be useful for life these heavier elements need to be bunched together somehow. If they're evenly dispersed they won't be useful.

That said, the problem of complex molecules dispersing before they have chance to form into something living is very real. While Earth life presumably overcome the dispersal problem in our planet's waters the problems in doing this in a gas giant atmosphere do seem considerably greater.

[Adrian Laguna]

Although the percentage of heavier elements like carbon may be very small in a gas giant, gas giants are HUGE so the absolute amounts of such eelements may exceed those found on a small, rocky planet like ours. Of course, to be useful for life these heavier elements need to be bunched together somehow. If they're evenly dispersed they won't be useful.

That said, the problem of complex molecules dispersing before they have chance to form into something living is very real. While Earth life presumably overcome the dispersal problem in our planet's waters the problems in doing this in a gas giant atmosphere do seem considerably greater.

The chaotic nature of interactions in a gas giant's atmosphere, both at the micro and macro scales, could potentially create areas of high concentration of organic compounds. Taking a look at Jupiter's atmosphere, one can see that the there is considerable variance in the colouring of various areas, particularly within the cyclones. This would suggest that there are differences in the chemical and/or physical composition of these areas. Thus it is not unreasonable to think that chance might eventually over come the dispersal problem.